


Bausch & Lomb 
Balopticons 


C. W. Courtney Company 
731 South Hope St. | 
Los Angeles, California 









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Balopticons and 


Accessories 





Copyrighted 1920, by Bausch & Lomb Optical Co. 
Revised Sept. 1923, and Feb. 1924 


Bausch & Lomb Optical Co. 


ochiester, aN aie 


New York Chicago San Francisco 
Washington London 


- DD-5, I-24, 7M 


Branches and Forein Agencies 


We maintain branch offices in New York, Chicago, Washington and San 
Francisco, where sample lines of our products are carried for the inspection 
of our customers. Our representatives will be found well versed in all the 
phases of our business, glad to extend every courtesy and to give any desired 
information. 


Our products are supplied also by dealers in the United States and Can- 
ada and by our agents in foreign countries. 


Branches 


NEW YORK: Bausch & Lomb Optical Co., Pershing Square Building, Park 
Avenue and 42nd Street. 


WASHINGTON, D. C.: Bausch & Lomb Optical Co., 613 Fifteenth St. N.W. 
Cuicaago, Iuu.: Bausch & Lomb Optical Co., 5 No. Wabash Ave. 
SAN FRANcIScOo, CAu.: Bausch & Lomb Optical Co. of Cal., 28 Geary St. 


ENGLAND, Lonpon: Bausch & Lomb Optical Co., Ltd., 37 and 38 Hatton 
Garden, E. C. 


Foreign Agencies 


AUSTRALIA, SYDNEY, N.S. W.: Donald Ross & Co., Ltd., Angel Place, off 
12 ea itte st. 


BRAZIL, RIO DE JANEIRO: J. Pinho, Caixa Postal 1126. 
CHINA, SHANGHAI: Edward Evans & Sons, Ltd., 30 North Szechuen Road. 
ITALY, MILANO: Henry Coe & Clerici, Via Settembrini 11. 

Andrews & George Co. 
JAPAN . TOKYO: Central P. O, Box F-25 

OSAKA: 119 Nichome Yedobori, Minanidori, Nishiku. 

KOREA, SEOUL: Andrews & George Co. 
MANCHURIA, DAIREN: Andrews & George Co. 
PHILLIPINE ISLANDS, MANILA: Clark & Co., Escolta 90-94. 
NEW ZEALAND, WELLINGTON: Waterworths Limited, 286 Lambton Quay. 


BAUSCH & LOMB OPTICAL CO. 


EXECUTIVE OFFICE AND MANUFACTORY 


ROCHESTER, N. Y. 





*j Lic Poems ¢ ge, $ — 
TH 7 CENTER 


Preface 


Although this is not a complete catalog of all our projection line, in 
that it does not include our micro-projection apparatus and other instru- 
ments for special work, it contains all the models required for ordinary 
projection purposes. We shall be glad to send our complete projection 
catalog, or information concerning any equipment not listed here, upon 
request. 


During the remarkable development of motion pictures in recent years 
“still” projection has more than held its own. It is today more widely 
recognized than ever before as a necessary adjunct to the more serious 
purposes of visual instruction and entertainment. ‘To meet all the varied 
requirements of both purposes in the most efficient manner possible has 
been our constant aim throughout the twenty years in which we have been 
developing this line. 


The user of projection apparatus will find in the following pages much 
information of interest and value regarding the various possibilities and 
applications of optical projection. 


The trade name, ‘‘Balopticon’’, by which we designate our lanterns, has 
long since become standardized among those interested in the highest grade 
projection apparatus. The prefix, ‘“‘Bal’’, is derived from the Greek verb, 
“ballein’’, meaning to throw or project. Incidentally it contains the 
initials of our company and is rightfully used only by us. 


Back of our projection apparatus, as all of our products, are nearly 
seventy years of scientific and productive experience as optical manufactur- 
ers. The different instruments offered have resulted from the combined 
efforts of our Scientific and Technical Bureaus, working constantly in co- 
operation with the users of such apparatus, whose suggestions are always 
given serious attention. 


In the actual manufacture we enjoy the advantage of producing practi- 
cally all parts, mechanical as well as optical, in our own works. This now 
includes our basic raw material, optical glass, the manufacture of which we 
successfully developed, before and during the war, for the first time in Amer- 
ica. We are thus enabled not only to assure the effective co-ordination of 
the different parts, but to give all of our Balopticons and accessories the 
unqualified guarantee which our name conveys. 


BAUSCH & LOMB OPTICAL CO. 


Terms 


When ordering from this catalog, please give catalog number, name of 
article and size. Use code words in telegraphing. 


Credit and Financial Standing. To avoid delay, purchasers with 
whom we have no account and who have no mercantile rating, should ac- 
company their first order with commercial references or remittance in cash, 
money orders, or New York or Chicago current funds, as your local check 
may be subject to collection charges. 

Under an arrangement made by the Western Union Telegraph Co. orders 
can now be sent by telegraph between points in the United States, in the 
same message with remittance. Code words or catalog numbers may be 
used. Information may be secured on application to nearest Western Union 
manager. 


Cc. O. D. Shipments. No C. O. D. shipments will be made unless 
sufficient funds to cover delivery charges both ways accompany the orders. 
Goods made on special order, or to be sent on memorandum account, will not 
be forwarded C. O. D. 


Quotations. Our prices are f. o. b. Rochester, N. Y. Transportation 
for goods sent on memorandum or for examination is at the expense of the 
customer. 


Liability. In packing we double check all goods, and obtain proper 
receipts from the transportation companies. Unless otherwise specified, we 
shall use our best judgment in mode of shipping, prepaying transportation if 
requested and adding amount to invoice. Our responsibility ceases when we 
have delivered a shipment to the carriers. All claims for breakage should be 
reported to the transportation companies at once, as we cannot be held 
responsible for losses or damage to goods in transit. Please examine all pack- 
ing minutely for small items. 


Guarantee. We exercise the utmost care in manufacturing and pack- 
ing. In case of faulty goods inadvertently reaching our customers, we shall 
feel under obligation if our attention is called thereto. 


Returning of Goods. Goods being returned for any reason should be 
plainly tagged with the sender’s name and address. Special identification 
tags are furnished on request. Wherever possible, please give date of invoice 
on which the goods were originally billed. 

Notice. Prices in this catalog are subject to change without notice. We 
make no charge for boxing or packing and no allowance for freight, express 
or parcel post charges. 


BAUSCH & LOMB OPTICAL CO 





BAUSCH & LOMB OPTICAL COMPANY 








Introductory 


HILE optical projection, in a crude form, was known as far back as 
1700, its scientific and universal application is of comparatively re- 
cent development. Unappreciated and undeveloped for generations, it has 
come into its own at last, till today it is an agency of widely known value 
in the scientific and educational world and in many other fields of usefulness. 


A projection lantern is now a recognized necessity in every completely 
equipped church, Sunday school, school or lecture hall. Since there are 
models that project either lantern slides or opaque objects, or both, their 
range of usefulness is very wide. 


The bodies of our Balopticons are of sheet metal, stamped 
out by special forming tools, making a light but durable 
instrument. They are finished with a dull, black lacquer thoroughly baked 
in a high temperature oven. This treatment produces a rich, black finish 
which is both serviceable and appropriate. 


Construction. 


There are a number of different illuminants that can be 
utilized to supply the light for projection purposes: the 
gas-filled Mazdas, the most recently and highly developed; the hand-feed 
arc lamp; and the acetylene burner. Wherever possible, we recommend 
that a Mazda lamp be used, for such a lamp is the most convenient to 
operate and gives the best results. The 6-volt lamp, for use with a storage 
battery, makes possible the use of a Mazda lamp even where electricity is 
not available. 


Illuminants. 


The condensing lenses play an important part in the optical 
system of any projection apparatus, as the uniformity of illumi- 
nating and the size of the illuminated field are dependent on the 
purity of the glass they are made from and on the correctness of their focal 
length. The condensing system furnished with the Balopticons shown in 
this catalog is a double system, consisting of two plano convex lenses with 
the convex sides facing each other. 


Optical 
Parts 


Improvements on the optical parts of our Balopticons have been in 
keeping with the mechanical development, as evidenced by our series of 
Balo projection lenses. These superior objectives are of an entirely new 
type of construction, particularly well corrected for flatness of field and 
critical definition. They are made in three series as described under 
‘‘A ccessories.”’ 


In purchasing an apparatus for the projection of either lantern 
slides or opaque objects a point which should receive careful 
attention is the selection of an outfit with the correct focal 
length of lens to meet the specific requirements satisfactorily. The focal 
length of the projection lens, all other conditions being equal, determines 
the size of picture on the screen. In selecting an apparatus, therefore, one 


Hi 


Size of 
Picture 














should determine the distance at which the lantern is to be placed from the 
screen and the size of picture desired. With these two factors given, the 
focal length of lens required can readily be determined by reference to one 
of the tables here given. 

We would particularly caution Baloptican users not to make the mistake, 
too often made when working with a projection lantern, of deciding upon too 
large a picture. Any picture out of proportion in size to the distance at 
which it is being viewed appears unnatural and lacking in perspective and 
is a strain to the eyes of the observer. 

Where the regular lighting circuits are available, lamps for 110 
volts are ordinarily used. For higher voltages, the 220-volt resistance, 
p. 40, must be used in series with the lamp, as it has not been found practical 
to make this type of lamp for high voltage, since that would necessitate the 
use of a more fragile filament and a larger light source. 

The focal lengths here tabulated are those which are listed with some 
one of our different Balopticons for either lantern slides or opaque objects. 
The tables give in feet the length of one side (the longer in case of lantern 
slides) of the screen image to be obtained at the different projection dis- 
tances and with the different lens foci indicated. 


Table 1: For Lantern Slides, 234 x 3-inch Mat Opening 


Distance from Lantern to Screen 





Focus of Lens 




















15 ft.| 20 ft.| 25 ft.| 30 ft.| 35 ft.) 40 ft.| 45 ft.| 50 ft./ 60 ft.) 70 ft.| 80 ft. 
6-inch 744 | 10 12% 
8-inch 544| 7%| 94%) 11%) 13 15 
10-inch 44| 6 1419 104% | 12 13% 
12-inch 5 644 | 74%| 834] 10 1144 | 12%] 15 
15-inch 4 5) 6 7 8 4) 10 12 14 16% 
18-inch 5 534 | 644| 714%] 8%) 10 li yds 


Example:—A 10-inch lens used at a distance of 40 feet from the screen will project an 
image measuring 12 feet on its longer side. 





Table 2: For Opaque Objects, 6 x 6-inch Opening 








Distance from Lantern to Screen 





Focus of Lens 











15 ft. | 20 ft. 25 ft. 30 ft. 35 ft. 
15-inch 54% 7% 9% 11% 
18-inch 414 6 8 914 Tt 





See page 34 for longer focus lenses. 


For lantern slide projection only the white opaque screens will be found 
entirely satisfactory. With such a screen the room need be only partially 
darkened. When projecting opaque objects we strongly recommend the 
use of an aluminum coated screen, as that will materially increase the 
brilliancy of the image. The room in which such an apparatus is used 
should be totally darkened. 








BAUSCH & LOMB OPTICAL COMPANY 








Balopticon Model A 


In simplicity, compactness 
and portability, this little in- 
strument is unexcelled for lan- 
tern slide projection in class 
rooms, small auditoriums, and 
in the home. While it is a 
truly portable lantern, none 

) of the optical and mechanical 
features so essential to best projection results have been sacrificed. 

Essentially this instrument is constructed along the lines of our Model B 
Balopticon, which has long occupied a premier position among small lantern 
slide projectors. It has the same lamp housing, lamp, reflector and optical 
parts, but the carrying case is an integral part of the equipment, serving as a 
supporting base and bellows when the lantern is in operation. 





The Balo projection lens, of 12-inch focus and 12 or 232. inch diameter, 
is fastened to a plate behind a spring door which opens in the front of the 
case. It is adjustable by means of a spiral focusing mount. On the rear 
of the case is a door which lets down to a horizontal position, allowing the 
lamp house easily to slide in and out of the case on metal tracks, a stop being 
provided to give it the correct location for use with the 12-inch focus lens. 


In front of the lamp housing are mounted the two plano-convex condens- 
ing lenses. They are 432, inches in diameter, sufficiently large to illuminate 
evenly the entire surface of the slide. 

The case, when closed, measures 131% inches long, 11 inches high and 
61% inches wide. It is provided with a strong handle and because of the 
even balance of the outfit is extremely easy to carry. 























Code Word Cat. No. Specifications Price 





Daabs AM 12q Model A Portable Balopticon with 110-volt, 400- 
watt Mazda lamp with ground and polished glass 
reflector; 15 feet of extension cord and connect- 
ing plug; 15 in. diam., 12 in. focus projection 
lens; 4;°; in. condensers; double slide carrier and 


carrying case. $70.00 
Daact AM 12 Same, but with 25-in. diam.., ‘12-in. focus lens. 75.00 
Daadv AM 6V 12q Same as AM 12q but with 6- ‘volt, 24-watt Mazda 

lamp for use with storage battery. . st: 67.00 
Daafw AM 6V 12 Same, but with 2;5 in. diam., 12-in. focuslens... .. 72.00 


Daahy AM 30V 12q) Model A Portable Balopticon, as described, but 
with 30-volt, 14-ampere Mazda lamp for use on 
individual Bene circuits, 1% in. diam., 12 in. 








focus lens. . us 75.00 
Duajz AM 30V 12 | Same, but with Qi in. diam., 12 in. focus lens. . 80.00 
Daakb AG 12q Model A Portable Balopticon as described, but 

with acetylene burner, 15 in. diam., 12 in. focus 

lengins id: Sclode sactina Merc eae ee ie ee 67.00 
Daalc AG 12 Same, but with 2;5 in. diam., 12 in. focuslens.. ... 72.00 


9 











BAUSCH & LOMB OPTICAL COMPANY 











Model B Balopticon 


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a 
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Model B with Mazda Lamp and 2;;-Inch Diameter Lens 


This compact, efficient little instrument met with instant success when 
placed upon the market a few years ago and has increased in popularity con- 
stantly until it is now one of the most widely known for use with lantern 
slides only in school rooms, small auditoriums, Sunday school rooms, lodges 
and in the home. Because of its demonstrated merit it has been adopted as 
standard equipment by several organizations which distribute large numbers 
of lanterns. 

It is constructed throughout of a substantial weight of sheet metal, the - 
various-parts being made with special forming tools, thus providing light- 
ness in weight, rigidity and durability. The finish is a smooth black through- 
out. 

The top of the lamp house is removable, permitting easy access to the 
illuminant, and the base is provided with an adjustable plate in which may 
be interchanged the 400-watt, 110-volt lamp, which is entirely silent and 
automatic, and can be attached to any ordinary lamp socket, the 6-volt lamp 
or the acetylene burner. The 30-volt, 14-ampere lamp requires a special 
plate, as it must be provided with a mogul socket. 

The condensing lenses, two plano-convex, fit in a square mounting con- 
necting the lamp house and slide carrier support. Each condenser is held 
in place by a metal guide, while the hinged cover of the mounting has two 
clips, which hold the condenser in position and prevent their shaking about 
during shipment. The cover is fastened down by a small set screw. 

Our well-known Balo projection lenses are supplied with this instrument 
They are made in diameters of either 1°, or 27° inches. The former are 
made in 6, 8 and 10-inch focal lengths, mounted in either a spiral or rack and 
pinion focusing mount, and the latter in 10, 12 or 15-inch focal lengths, in 
rack and pinion focusing mount. The larger diameter is particularly re- 
commended, because of the fact that the illumination is increased approxi- 
mately 40 per cent. over that of the smaller diameter. 

A very compact metal case, into which the lantern may be easily placed, 
is regularly supplied with each equipment, affording an easy means for carry- 
ing the instrument and a dust-proof cabinet in which to store it when not in 
use. 








BAUSCH & LOMB OPTICAL COMPANY 








Specifications 


Base—Consists of front and rear metal standards, front standard fitted with 
elevating device, carried on sliding rods which have extension to accom- 
modate 15-in. lens. 

Lamp House—Of sheet metal with special ventilation; measures 614 x 7 x 5 
in. with removable top; all illuminants interchangeable in one housing. 

Illuminant—Our 400-watt, 110-volt, gas-filled Mazda lamp, 30-volt, 14- 
ampere Mazda, 6-volt Mazda, or two-jet acetylene burner. 

Condensing System—Our regular double system, 4;5-in. diameter, in 
special ventilated mount from which lenses can be easily removed for 
cleaning. 

Slide Carrier—Our double carrier, No. 4430, with elevating device. 

Bellows—Mounted on metal frames which slide in metal ways. 

Projection Lens—Balo lens of 15¢ or 2;5-in. diameter and of focus as 
listed below. 

Dimensions—Length (ready for operation), 22 in.; height, 934 in. 

Weight—Complete in case, 13-15 lbs., depending on equipment. 

Case—Sheet metal, 7144 x 91% x 15 in., lacquered in black; with carrying 
strap. 

*The quick changing slide carrier, No. 4449, giving a dissolving effect, may be substi- 


tuted for $3.00 extra. Wecan supply to order carriers for small slides, so that one may use 
either the standard slide or the special small size now being offered. 


With Mazda Lamp 











Code Word | Cat. No. Specifications Price 








Dhurj BM 6qs | Model B Balopticon with 400-watt, 110-volt Mazda 
lamp, with ground and polished glass re- 
flector; 15 feet of extension cord with connecting 
plug and switch; double slide carrier; metal carry- 
ing case; and 154-in. diam., 6-in. focus projec- 








tion lens in spiral focusing mount.............. | $54.00 
Dhusk BM 8qs | Same as above, but with 8-in. focus lens......... 54.00 
Dhutl BM 10 qs _ | Same as above, but with 10-in. focus lens........ 54.00 
Dhuom BM 6q Same as above, but with 6-in. focus projection lens 

in rack and pinion focusing mount.............. 57.00 
Dhuxp BM 8q Same as above, but with 8-in. focus lens........ 57.00 
Daanf BM 10q Same as above, but with 10-in. focus lens........ 57.00 
Daapg BM 10 Same as above, but with 2;7;-in. diam., 10-in. focus 

projection lens in rack and pinion focusing mount | 65.00 
Daarh BM 12 Same as above, but with 12-in. focus lens........ 65.00 
Daasj BM 15 Same as above, but with 15-in. focus lens........ 65.00 
Daatk BM 30 V10 |} Model B Balopticon with 30-volt, 14-ampere (420- 


watt) Mazda lamp with ground and polished glass 
reflector; 4 feet of extension cord with switch and 
connector; double slide carrier; metal carrying 
case; and 2;-in. diam., 10-in. focus projection 


lens in rack and pinion focusing mount.......... 70.00 
Daal BM 30 V12/| Same as above, but with 12-in. focus lens........ 70.00 
Daazn BM 30 V15| Same as above, but with 15-in. focus lens........ 70.00 
Daazr BM 6V10!| Model B Balopticon with 6-volt Mazda lamp with 


silvered globe, supplementary condenser and six 
feet of extension cord fitted with switch and con- 
necting lugs for attaching to storage battery; 
double slide carrier; metal carrying case; and 2;3- 
in. diam., 10-in. focus projection lens in rack 





ANd pINion 1OCUsINS MOUND.) cscs eee ee or 63.00 
Daebt BM 6V12| Same as above, but with 12-in. focus lens........ 63.00 
Daecy BM 6V15| Same as above, but with 15-in. focus lens........ 63.00 


tig 








Code Word 


Daedw 


Daegy 
Daehs 


BAUSCH & LOMB OPTICAL COMPANY 


Cat. No. 


BG 10 


BG 12 
BG 15 











With Acetylene Burner 











Specifications 


Model B Balopticon with two jet acetylene burner, 


fitted with ground and polished glass reflector and 
6 feet of rubber hose; double slide carrier; metal 
carrying case; and 2;;-in. diam., 10-in. focus 
projection lens in rack and pinion focusing mount 
Same as above, but with 12-in. focus lens........ 
Same as above but with 15-in. focus lens ........ 














Illuminants for Model B Balopticon 


No. 4461 


No. 4462 No. 4502 





Price 

















Code Word 


Cat. No. 


Specifications 





Daemf 


Daeng 


Daeph 


Daerj 





4461 


4462 


4515 


4502 





400-watt Mazda Lamp with reflector, socket, 15 feet 
of extension cord, connecting plug and switch for 
use on Model. B. «2 .....20.p4) 03); 10 oe 
2-jet Acetylene Burner with ground and polished 
glass reflector, mounted on a base to interchange 
with socket for 400-watt lamp on Model B; with 6 
feet of rubber. hose... ... 1...) . 52) 
30-volt, 14-ampere (420-watt) Lamp with re- 
flector, mogul socket and clamp for attaching to 
sliding plate on bottom of lamp house, 4 feet of ex- 
tension cord and connector for use on Model B.. 
6-volt Mazda Lamp with silvered bulb supple- 
mentary condenser on support to interchange with 
socket of 400-watt lamp, 6 feet of extension cord, 
switch and connecting lugs... .. . i... @oeeeee 








Price 





$13.50 


10.50 


18.50 


11.50 


NotE—To those who desire a 30-volt lamp to interchange with the regular 110-volt, 
400-watt lamp, we can supply a 30-volt, 250-watt lamp with medium screw base 
at the same price as the regular 400-watt lamp. 


For extra bulbs see page 38. 


12 





BAUSCH & LOMB OPTICAL COMPANY 











Special Travelling Outfits 


. The Model B Balopticon naturally ap- 

peals to those who travel with a stereopti- 
con because of its compactness and light 
weight. For this purpose we have designed 
a special carrying case of wood covered 
‘with leatheret, with metal corners and 
locks. This outfit can be shipped as bag- 
- gage or by express with perfect safety. 
Space is provided in this case for the 
Balopticon, together with a separate com- 
partment in which an acetylene burner, 
an extra Mazda lamp or a quantity of 
slides may be carried. The top of the case 
is fitted with a partition to form a compart- 
ment in which a sateen screen may be car- 
ried. 
Another feature of this portable equip- 
ment is the accessory carrying case for a 
10-cu. ft. acetylene tank, which may be 
attached to the bottom of the regular 
carrying case for use when one is traveling 
where electricity is not available. 

In many cases the traveling lecturer will be unable to obtain a table of 
suitable height for the support of the lantern, so we have arranged to utilize 
the case for this purpose by attaching to its end the board which forms the 
compartment for the screen. The elevating rods fitted to the front standard 
of the Balopticon make it possible to tip the lantern to bring the picture on 
the screen. 



























Code Word | Cat. No. Specifications Price 
Daejb BMP 12 Model B Balopticon with 400-watt, 110-volt Mazda 


lamp, 27;-in. diam., 12-in. focus lens in rack 
and pinion mount; in special carrying case of wood 
covered with black leatheret, with metal corners 
aNdalOGKS fiery nate ae aa amet eh ee es EN $92.50 
Diacs BMP 6V12 | Same as above, but with 6-volt, 24-watt Mazda lamp 
in place.of the 400-watt lamp..............:.--. 90.50 
Daekce BGP 12 Same as above, but with double-jet acetylene burner 
in place of Mazda lamp and with special glass re- 
Hector fittedm lamp house...) q.ceuer eee 89.50 
Diabr BMGP 12 | Model B Balopticon with 400-watt, 110-volt Maz- 
da lamp and with acetylene burner to interchange 
with Mazda lamp; with lens and carrying case as 








described above: pati wk. Nees cae tet eae ee 102.00 
Daeld 4529 Accessory Carrying Case for 10-cubic-foot acetylene 
tank-as described! svia-y. oe ae ee ee 17.50 





NOTE—We are listing with this outfit the 12-inch focus lens, which is the one generally 
required. The 10 or 15-inch focus lens can be supplied at the same price. If one of these 
is preferred, substitute “10” or ‘15’ for the numeral ‘'12” in the above catalog numbers. 

We recommend that an extra Mazda lamp be included in traveling outfits to guard 
against possible breakage or burning out. For prices see page 38. 


13 











BAUSCH & LOMB OPTICAL COMPANY 








Model BC Balopticon 





Model BC with Mazda Lamp and 2;%-Inch Diameter Lens 


This new Balopticon follows the general lines of Model B, but is enough 
larger to accommodate the 600-watt tubular-shaped. Mazda lamp—the 
most powerful illuminant allowed on an ordinary lighting circuit by the 
Board of Underwriters. With this lamp, the only illuminant regularly 
supplied for this model, ample illumination is provided for screen images up 
to 12 feet in width. The highly corrected Balo projection lenses are fur- 
nished in either 10, 12, 15 or 18-inch focal lengths, depending upon the 
projection distance and the size of the picture required. 


A spherical glass reflector with a mounting by means of which it is attached 
directly to the lamp bulb is supplied, thereby assuring the user of the great- 
est efficiency from the Mazda lamp. 

This instrument is highly recommended and will prove an ideal instru- 
ment for class rooms and moderate sized auditoriums where the regular 
110-volt lighting system only is available. 


Specifications 


Base—Consists of front and rear metal standards, front standard fitted with 
elevating device, carried on sliding rods which have extension to accom- 
modate 15-in. lens. 


Lamp House—Of sheet metal with special ventilation; measures 934 x 7144 
x 8 in., with removable top; all illuminants interchangeable in one 
housing. 


Iluminant—Our 600-watt, 110-volt, tubular-shaped, Mazda lamp. 


Condensing System—Our regular double system, 4;%-in. diameter, in 
special ventilated mount from which lenses can be easily removed for 
cleaning. 


*Slide Carrier—Our double carrier, No. 4430, with elevating device. 
Bellows—Mounted on metal frames which slide in metal ways. 


14 





BAUSCH & LOMB OPTICAL COMPANY 








Projection Lens—Balo lens of 2;-in. diameter, and of 10, 12, 15 or 18-in. 
focus. 


Dimensions—Length (ready for operation), 26-in.; height, 13 in. 
Weight— Without case, 141% lbs. 


Case—Can be used as carrying case or dust-proof cabinet. 
*The quick changing slide carrier, No. 4449, giving a dissolving effect, may be sub- 


stituted for $3.00 extra. We can supply to order carriers for small slides, so that one may 
use either the standard slide or the special small size now being offered. 


Code Word | Cat. No. Specifications Price 





Daesk BCM 10 | Model BC Balopticon with 600-watt, 110-volt, tu- 
bular-shaped Mazda lamp, with ground and 
polished glass reflector; 15 feet of extension cord 
with connecting plug and switch; double slide 
carrier; metal carrying case; and 2;;-in. diam., 
10-in. focus projection lens in rack and pinion 


TOCISING NOUN tanta ey ee ani eee eon eae So $75.00 
Daetl BCM 12 | Same as above, but with 12-in. focus lens........ 75.00 
Daevm BCM 15 | Same as above, but with 15-in. focus lens........ 75.00 
Daexp BCM 18 | Same as above, but with 18-in. focus lens........ 77.00 


15 





BAUSCH & LOMB OPTICAL COMPANY 








Model BB Dissolving Balopticon 





Model BB with Dissolving Rheostat and 2;3;-inch Diameter Lenses. 


It is an accepted fact that the most pleasing way of projecting lantern 
slides is with a dissolving view lantern, by means of which the “racing” of the 
slide across the screen or a short interval of darkness between slides is entire- 
ly eliminated. This not only relieves eyestrain, but the dissolving of one 
view into the succeeding one produces a very pleasing effect. 


A number of devices have been produced for use on a single lantern for 
which claims of producing dissolving views have been made, but they either 
show movement of the slide upon the screen or produce momentary darkness. 
True dissolving effects can only be produced by the use of two lanterns fitted 
with a device by means of which the pictures are projected alternately by one 
lantern and then the other. 


Believing that this feature in a projecting lantern makes a strong appeal, 
we have designed the Model BB Balopticon, which is very compact and 
extremely simple to operate. This is truly two lanterns in one, as there 
are two light sources and two complete optical systems side by side in the one 
lantern body. This construction makes possible the maximum compact- 
ness and eliminates the setting up and adjusting of the average double dis- 
solving lantern. No more adjustments are required than in the ordinary 
lantern, except the adjustment of the lenses by means of sliding plates on the 
front standard, so that the pictures are superimposed on the screen. By 
means of the construction employed the complete equipment can be put in 
one carrying case—a decided advantage to travelling lecturers or to those 
who cannot leave their apparatus permanently installed. 


The dissolving effect, or the change from one picture to the next, is ac- 
complished by a resistance with sliding contact, which gradually cuts off the 
current to one lamp and turns it on in the other at a corresponding rate so 
that the screen is never dark. The effect produced with this device is a very 
pleasing one because there is no abrupt change, as one picture gradually dis- 
solves into the succeeding one. 


Two 400-watt Mazda lamps are used, but due to the particular way in 
which they are connected up, there are never more than 400 watts drawn at 


16 











one time, so that the apparatus requires only one lead of wire and can be 
connected to any regular lighting socket. In addition to this advantage the 
cutting off of the lamp when not required increases the length of service and 
materially reduces the heat. 


Specifications 


Base—Consists of front standard supporting projecting lenses, and sliding 
rods connecting with lamp house. 

Lamp House—Of sheet metal, specially ventilated, with removable top fo1 
access to lamps; measures 7 x 95% x 1014 in. 

Illuminant—Two 400-watt gas-filled Mazda lamps with glass reflectors 
connected with dissolving rheostat. 

Condensing System—Two regular double systems, 435 in. diameter, in 
special ventilated mount from which lenses can be easily removed for 
cleaning. 

Slide Carrier—Permanently fastened in front of condensing system, with 
grooves for either American or English size of slide. 

Bellows—Mounted on metal frames which slide in metal ways. 

Projection Lens—Two of our regular Balo lenses, either 15¢ in. diameter or 
2°; in. diameter, as desired. 

Dimensions—Length (ready for projection with 15-in. focus lenses) over 
all, 261% in. 

Weight—Complete in case with 23% in. diameter lenses, 30 lbs. 

Case—Sheet metal, 15% x 10% x 1014 in., lacquered in black; with hinged 
side door, two catches and carrying strap. 





Code Word | Cat. No. Specifications Price 


Daigz ‘| BBM 10q | Model BB Dissolving Balopticon with two 400- 
watt, 110-volt Mazda lamps with ground and 
polished glass reflectors; two 154-in. diam., 10-in. 
focus projection lensesin rack and pinion mounts; 
dissolving rheostat with 15 feet of extension cord, 
switch and connecting plug; metal carrying case |$134.00 





Dathb BBM 10 Same as above but with 2;,-in. diam., 10-in. focus 
projection lenses ei 7..u yc ee ee ee 150.00 
Daikd BBM 12 Same as above but with 12-in. focus projection 
lenges etc yy ties at eee ae ee ee ee 150.00 
Dailf BBM 15 Same as above but with 15-in. focus projection 


lonsés.y. 23 See as Ce ee eee 150,00 





i 











Stereoscopic Projection with Model BB Balopticon 


The Model BB Balopticon can be used for stereoscopic projection as 
well as regular projection purposes. Two slides, made from stereoscopic 
negatives, are used, the two pictures being superimposed on the screen. A 
blue-green glass filter is placed over one lens and a red glass filter, the com- 
plement of the blue-green, over the other lens, while the screen is viewed 
through spectacles having red and green lenses corresponding to the filters 
over the lenses. 

True stereoscopic effect is produced in this manner, objects appearing in 
correct relation to each other. This apparatus will be found of particular 
value in the departments of Biology, Anatomy and the like, where the third 
dimension is of such vital importance. When using the instrument for this 
purpose, the dissolving resistance must be eliminated, as both lamps have 
to be operated at full brilliancy, which is accomplished by means of an extra 
extension cord. 














Code Word | Cat. No. Specifications Price 
Daimg 4262 Pair of Complementary Glass Filters, one red 
and one green, in mountings to fit on front of pro- 

jection lens...) 0s a ee $7.50 

Dainh 4264 Pair of Spectacles with red and green lenses... . 2.25 

Daipj 4266 Extension. Cord. . ) 20. 0.5....4..: 310 Lvs 





18 








BAUSCH & LOMB OPTICAL COMPANY =) 








Model C Balopticon 





No. CA 10—Model C with Arc Lamp 


The Model C Balopticon was the first projection lantern to be made en- 
tirely of sheet metal by means of forming tools. It at once met with general 
approval and is still one of the most popular instruments for lantern slide 
projection. 


The interchange of illuminants has been made very simple, as each of the 
various illuminants is provided with a saddle support which slides on the 
two rods at the side of the lamp house. The rear of the lamp house is fitted 
with a hinged shield or door, which may be raised and the illuminant with- 
drawn for adjustment or interchange. 





7 eee 
i e 
as 


No. CM 10—Model C with Gas-Filled Mazda Lamp 





Five different illuminants, the 90° hand-feed arc lamp, 400-watt, 110- 
volt Mazda lamp, 30-volt, 420-watt Mazda lamp, 6-volt, 24-watt Mazda 
lamp and the acetylene burner, all fitted with a base providing ready inter- 
changeability, may be used with this equipment. The 400-watt, 110-volt 
lamp is recommended for general use where electricity is available, while 
the 30 volt, 420-watt lamp can be used on individual lighting plants and 
the 6-volt, 24-watt lamp or acetylene burner where electricity is not avail- 
able. For long distance projection, where a large picture is to be projected, 
the arc lamp, which must be used with a rheostat, is recommended. Selec- 
tion of the rheostat should be made according to conditions. See page 39. 


19 





BAUSCH & LOMB OPTICAL COMPANY 











The projection lenses are of our Balo series, the highest grade lenses made 
for lantern slide projection. They are made in two diameters for use with 
the arc lamp, 154 and 2; in., but the 235 in. is recommended for use with 
the other illuminants. 





Double Dissolving Model C with Are Lamps 


Two Model C units can be connected, one above the other, as shown in 
the above illustration, by means of special connecting parts and the lenses 
fitted with a pair of iris dissolvers so arranged that one diaphragm closes as 
the other opens. If the 400-watt, 110-volt Mazda lamp is used, the dis- 
solving rheostat regularly supplied with the Model BB can be used instead 
of the iris diaphragm. Either of these combinations produces a perfect dis- 
solving effect, making such an equipment ideal for auditorium use. As the 
two units can be easily,disconnected, they can be used also as single lanterns 
in different rooms. 


Specifications 


Base—Consists of metal feet on bottom of lamp house and front metal 
standard of one piece with front board, the whole carried on sliding rods; 
front standard provided with elevating device for tilting instrument as 
desired. | 

Lamp House—Of sheet metal, fitted with our special, patent, light-tight 
ventilator and provided with two observation windows; measures 614 in. 
long, 11 in. high and 6 in. wide, asbestos lined. 

Illuminant—Hand-feed are lamp for direct or alternating current with 
adapters for small carbons, gas-filled Mazda lamp or acetylene burner. 

Condensing System—Our regular double system in ventilated mount; 
diameter, 43% in. 


20 











BAUSCH & LOMB OPTICAL COMPANY 








*Slide Carrier—Our double carrier, No. 4430, with elevating device. 


Bellows—Mounted on metal frames which slide in metal ways, with ex- 
tension sufficient for 18-inch focus lens. 


Projection Lens—Our Balo lens with rack and pinion adjustment. 
Dimensions—Length, extended, 27 in. without lens; height, 11 in. 
Weight—Alone, 14 lbs.; in case, 24 Ibs. 


Case—Of metal, neatly lacquered in black, measuring 2234 x 12 x 7 in. and 
provided with carrying strap. 


*The quick-changing slide carrier, No. 4449, giving a dissolving effect, may be substi- 
tuted for $3.00 extra. We can supply to order carriers for small slides, so that one may use 
either the standard slide or the special small size now being offered. 


With Arc Lamp 














Code Word | Cat. No. Specifications Price 
Dairk CA 8q | Model C Balopticon with hand-feed are lamp, 

double slide carrier, and 154-in. diam., 8-in. 

focus lens in rack and pinion focusing mount.... | $56.50 
Daisl CA 10q | Same as above, but with 10-in. focus lens........ 56.50 
Daitm CA 10 Same as above, but with 2;;-in. diam., 10-in. fo- 4 

CUS Projecticnslens a tes een ere ees 61.50 
Daivn CA 12 Same as above, but with 12-in. focus lens........ 61.50 
Daixr CA 15 Same as above, but with 15-in. focus lens........ 61.50 
Daizt | CA 18 Same as above, but with 18-in. focus lens........ 63.50 














With Mazda Lamp 























Code Word | Cat. No. Specifications Price 
Daobw CM10 Model C Balopticon with 400-watt, 110-volt 
Mazda lamp with ground and polished glass re- 
flector and 2;3-in. diam., 10-in. focus lens.... | $65.00 
Daody CM12 Same as above, but with 12-in. focus lens........ 65.00 
Daofz CM15 Same as above, but with 15-in. focus lens........ 65.00 
Daogb CM18 Same as above, but with 18-in. focus lens........ 67.00 
Daohce CM6V10 Model C Balopticon with 6-volt, 4-ampere lamp 
with silvered globe and supplementary condenser, 
and 2;;-in. diam., 10-in. focus lens.......... 61.00 
Daojd CM6V12 | Same as above, but with 12-in. focus lens........ 61.00 
Daokf CM6V15_ | Same as above, but with 15-in. focus lens........ 61.00 
Daolg *CM30V10 | Model C Balopticon with 30-volt, 14-ampere (420 
watts) lamp with ground and polished glass re- 
flector, and 2;;-in. diam., 10-in. focus lens.... 69.00 
Daomh CM30OV12 | Same as above, but with 12-in. focus lens........ 69.00 
Daonj CM30V15 | Same as above, but with 15-in. focus lens........ 69.00 
Daopk CM3OVI18 | Same as above, but with 18-in. focus lens........ 71.00 











*If an outfit with the 30-volt, 14-ampere lamp is to be used on the regular circuit, a 
transformer or rheostat must be used in series with it. See page 39. 


NOTE—For extremely long distances lenses of longer focus than those listed can be 
supplied on special order. Sizes up to and including 22-inch focus will be supplied at the 
same' price as the 18-in. lens. For longer focal lengths special fittings are necessary and 
an extra charge of $7.50 will be made. 


21 





BAUSCH & LOMB OPTICAL COMPANY 














With Acetylene Burner 


























Code Word | Cat. No. Specifications Price 
Daorl CG10 Model C Balopticon with double jet acetylene 
burner, ground and polished glass reflector and 

2,-in. diam., 10-in. focus projection lens... | $62.00 

Daosm CG12 Same as above, but with 12-in. focus lens... ... 62.00 

Daotn CG15 Same as above, but with 15-in. focus lens...... 62.00 








Double Dissolving Outfits 


In ordering a double dissolving outfit, prefix the catalog number with the 
word “Double.’’ The price of the double outfit will be twice that of the 
single instrument, plus $5.00 for the necessary connecting parts, and plus 
the cost of the iris dissolver or dissolving rheostat as may be required. Un- 
less otherwise specified, the iris dissolver will be supplied with all orders for 
this outfit. 




















Code Word | Cat. No. Specifications Price 
Dautp 4490 Iris Dissolver. 0.23001 Ls ee 
Dauzxt 4484 Dissolving Rheostat, with connecting cord... .. 30.00 








22 








BAUSCH & LOMB OPTICAL COMPANY 








Model CL Balopticon 





Model CL with Mazda Lamp 


The Model CL Balopticon, which has been especially designed for lantern 
slide projection at relatively long distances where large size pictures are 
required, is an ideal instrument for use in auditoriums or other large rooms 
where the lantern must necessarily be so placed with reference to the screen. 
It is fitted with a light-tight lamp house with hinged side door, which com- 
plies in every way with the Underwriters’ requirements for a housing for high 
power are lamps. Either a 90° hand-feed arc lamp, with which a maximum 
of 35 amperes of current can be used, or a 1000-watt, 110-volt Mazda lamp 
can be had for ordinary use. 

Ample illumination for pictures up to 12 feet in width is given by the 
1000-watt, 110-volt lamp, but for larger size pictures the arc lamp or the low 
volt Mazda with resistance is recommended. 

This apparatus is very substantially constructed throughout; the con- 
densers are mounted in a square frame, which connects the slide carrier 
support with the lamp house, thus making this part very rigid. Space is 
provided between the condensers for air cooling. A water cell can be in- 
serted if desired, and is recommended if the slides are to remain in place for 
an unusually long period of time. Each condenser is held in place by a metal 
‘guide in the frame, while the hinged cover of the mounting has clips to hold 
the condensers in position and prevent their shaking about during shipment. 
The cover is fastened down by a small set screw. 

A carrying case is not regularly supplied with this equipment, but one 
can be had as an extra. (See price list.) 

Two of these units can be connected, one above the other, as shown in 
the illustration, by means of special connecting parts, and the lenses 
fitted with an iris diaphragm dissolver or a dissolving switch, making an 
ideal dissuiving view equipment. The two units can be disconnected easily 
and used alone. 


23 





BAUSCH & LOMB OPTICAL COMPANY 











Double CLM Balopticon 


Specifications 


Base—Consists of metal feet on bottom of lamp house and front metal 
standard of one piece with front board, the whole carried on sliding rods; 
front standard provided with elevating device for tilting instrument as 
desired. 

Lamp House—Measures 134 in. long, 14 in. high and 71% in. wide, light- 
tight, constructed of double walls with air space between and provided 
with large light-tight door on the side—conforms to most rigorous re- 
quirements of Boards of Underwriters. 


Illuminant—Hand-feed arc lamp for direct or alternating current with 
adapters for small carbons, 1000-watt, 110-volt, gas-filled Mazda lamp, 
30-volt, 30-ampere (900-watt) Mazda. 

Condensing System—Our regular double system in ventilated mount; 
diameter, 41% in. 

*Slide Carrier—Our double carrier, No. 4430, with elevating device. 

Bellows—Mounted on metal frames which slide in metal ways, with ex- 
tension sufficient for 18-inch focus lens. 

Projection Lens—Our Balo lens with rack and pinion adjustment. 

Dimensions—Length, extended, 33 in. without lens; height, 14 in. 

Weight— Without case, 25 lbs. 


*The quick-changing slide carrier, No. 4449, giving a dissolving effect, may be substi- 
tuted for $3.00 extra. We can supply to order carriers for small slides, so that one may use 
either the standard slide or the special small size now being offered. 


24 








BAUSCH & LOMB OPTICAL COMPANY 








With Arc Lamp 


































































































Code Word | Cat. No. Specifications Price 
Daovp CLA 8q | Model CL Balopticon with hand-feed arc lamp; 
; double slide carrier; 154-in. diam., 8-in. focus 
projection lens in rack and pinion focusing mount | $89.50 
Daoxs CLA 10q | Same as above, but with 10-in. focus lens........ 89.50 
Daozv CLA 10 Same as above, but with 2;;-in. diam., 10-in 
LOCUS CNS 7 Fae Fie ere At Ee 6 oh een 97.50 
Daucy CLA 12 Same as above, but with 12-in. focus lens........ 97.50 
Daudz CLA 15 Same as above, but with 15-in. focus lens........ 97.50 
Daufb CLA 18 Same as above, but with 18-in. focus lens........ 99.50 
With Mazda Lamp 
Code Word | Cat. No. Specifications Price 
Dauge CLM 10 Model CL Balopticon with 1000-watt, 110-volt, 
Mazdalamp with ground and polished glass reflector 
and 2;3-in. diam., 10-in. focus projection lens | $95.00 
Dauhd CLM 12 Same as above, but with 12-in. focus lens........ 95.00 
Daujf CLM 15 Same as above, but with 15-in. focus lens........ 95.00 
Daukg CLM 18 Same as above, but with 18-in. focus lens........ | 97.00 
NOTE—For transformers or rheostat for these lamps see page 39. 
Carrying Case for CL Balopticon 
Code Word | Cat. No. Specifications Price 
Daurm 4376 Carrying Case of lacquered metal............... $9.00 
Dausn 4374 Water Gell .s.e.60 ie al ee ee eee 12.00 





Double Dissolving CL Balopticon 


When ordering a double dissolving outfit, prefix the catalog number with 
the word “Double’’. The price of the double outfit is twice that of the single 
instrument, plus $5.00 for the necessary connecting parts and plus the cost 


of the dissolving apparatus desired. Unless otherwise specified, 
dissolver will be supplied. 














Code Word | Cat. No. Specifications 
Dautp 4490 Iris Dissolver....... ee ee em ee ea See Oe 
Dauor 4487 Dissolving Switch with connecting cord.......... 





25 


the iris 











BAUSCH & LOMB OPTICAL COMPANY 








New Home Balopticon 





The New Home Balopticon has been designed primarily to meet the 
srowing demand for a thoroughly efficient and high grade apparatus for 
projecting post cards, photographs, solid objects, etc., in the home. Its 
scope, however, is not limited to the home. It is a very valuable asset for 
the schoolroom where it is possible to use the equipment within 9 to 12 feet 
of the screen in a room that can be well darkened. 


The outfit is made of sheet metal, finished in dull black, making it of 
light weight, but very durable. As the object holder occupies a horizontal 
position against the floor of the dark chamber, solid objects of many kinds 
can be projected on the screen. Pages from magazines and the like may 
be placed in position directly on top of the object holder and books or 
magazines which open flat may be readily placed in position. A single 
interior mirror brings the image always into correct position, from left to 
right, on the screen, so that reading matter appears unreversed. The 
exceptional strength of light makes this possible without detrimental loss of 
illumination. 

The lamp is a 400-watt, 110-volt, gas-filled Mazda, which can be 
attached to any ordinary lamp socket, operating automatically thereafter. 


The projection lens 1s of achromatic construction, designed to give maxi- 
mum illumination and a flat field. It projects a picture that is clearly de- 
fined to the extreme margin. An aluminum screen, 3 feet square, is included 
with the outfit. While a 3 ft. screen is regularly supplied, the illumination is 
sufficient for pictures up to 4 ft. in width with the 400-watt lamp. 














Code Word | Cat. No. Specifications Price 





Debot HRM-13 | Home Balopticon, for the projection of opaque 
objects only; with 400-watt, 110-volt, gas-filled 
Mazda lamp with specially corrected reflector, 
connecting cord and plug, and 3 ft. aluminum 








coated screen and two post card dolders....... | $50.00 
Debuv 5333 Metal Carrying Case. »:........... 9. 7.00 
Dhung 4378 Extra Post Card Holder~....... .. 53330 1.50 


Aluminum coated screen. 44% x 41% ft. in place of 3 ft. sereen, $4.00 extra. 


26 








BAUSCH & LOMB OPTICAL COMPANY 








Combined Junior Balopticon 


This Balopticon has been 
ldesigned to meet the popular 
demand for a really efficient but 
inexpensive instrument, for the 
projection of opaque objects as 
well as lantern slides for use 
before small groups in the class 
room, Sunday School and home. 


The interchange between the 
projection of opaque objects and 
of lantern slides is instanta- 
neous, being effected by simply 
turning a convenient lever on 
the outside of the dark chamber. 
This lever operates an interior shield which cuts off the light from the 
lens for either form of projection not desired at the time. 

The supporting base measures 314 in. from the table top to the bottom 
of the dark chamber and 13 in. between front and rear feet, so that ample 
space for the insertion of average size illustrations and objects is provided. 

The horizontal object support is securely held in place against the floor 
of the dark chamber by strong springs, so that sheets of paper, books, irregu- 
larly shaped objects, etc., are readily placed and held in position. To 
facilitate the handling of post cards, small photographs and the like, two 
holders, which slide through the object support, are provided. Highly 
polished interior reflectors are so placed to utilize the maximum amount of 
light striking the object. By means of a first surface reversing mirror, the 
image appears in correct position from left to right. 

The lenses are of achromatic construction, designed to give maximum 
illumination and a flat field,—that is, the picture produced is clearly defined 
to the extreme margin. 

An aluminum coated screen, 54 inches square, is regularly supplied with 
this instrument. However, in a totally darkened room it is possible to very 
satisfactorily project pictures up to six feet in width at a distance not 
greater than 15 feet. This unusually good illumination is made possible 
by the use of an especially efficient 110-volt, 400-watt Mazda lamp and a 
highly corrected optical system. A 30-volt, 420-watt lamp, furnishing 
greater illumination than the regular bulb, may be used with this apparatus 
when connected by a transformer to the regular 110-volt circuit. 








ae 


Code Word Cat. No. Specifications Price 




















Decar JCRM-13 Combined Jr. Balopticon for lantern slides, as 
well as for post cards, etc., complete with lan- 
- tern slide accessories, 400-watt, 110-volt, gas- 
filled Mazda stereopticon lamp, connecting 
cord and plug and 41%-ft. square aluminum 











SOTGOTI: ts Rees Lhe ae tae eee eRe ee ee $90.00 
Deces JCRM-30V-13| Combined Jr. Balopticon, same as above but 
with 30-volt, 14-ampere lamp in place of 400- 
watt. D1LO-voltisc ce oe tee oe ee ee eee 95.00 
Dexop 4499 Transformer for use on 110-volt alternating 
CUPLEN TA Me wee hee ee lain te ree ee 17.50 
Dhung 4378 Extra Post Card Holder .................. 1.50 
G.ftax 6 ft Screen >t eee extra 6.50 





27 








BAUSCH & LOMB OPTICAL COMPANY 








Combined Balopticon with 1000-watt 
Mazda Lamp 





CRM 18—Showing condenser in position for lantern slide projection. 


The constantly increasing demand for the Combined Balopticon with 
1000-watt Mazda lamp has demonstrated that there is a positive need for 
a simple but high-grade and efficient apparatus with which it is possible 
to project postcards, photographs, drawings, maps, solid objects and the 
like, as well as lantern slides. This instrument has proven itself to be the 
ideal equipment for the school and the church, both from an educational 
and entertainment standpoint. One of the reasons for its popularity is the 
fact that the 1000-watt lamp, which was especially designed for this appar- 
atus, makes it so simple to operate that even the most inexperienced in the 
use of projecting machines have no difficulty with this equipment. 


28 





BAUSCH & LOMB OPTICAL COMPANY 








Since, unlike the arc, the lamp is enclosed, it can be brought very 
close to the object without danger. By means of a mirror with very 
high optical corrections an unusually large percentage of the available 
spherical candle power is utilized. Because of this special application of 
the illuminant it is possible to project images of opaque objects with a 
brilianecy considerably exceeding that possible with a 35-ampere arc 
lamp on alternating current, and equaling that of a 20-ampere arc on direct 
current. 


The advantages of this lamp are obvious. It operates on only 9 amperes 
of current, which means a considerable saving in current consumption 
and makes it available for use on many outlets without the carrying capac- 
ity to supply high-power are lamps. No rheostat is necessary with it, 
and, what is the most striking advantage of all, the lamp is entirely auto- 
matic, requiring no attention whatever. It works equally well on direct or 
alternating current, and the disagreeable noise so characteristic of the 
alternating current arc is absent. A final advantage is that the quality or 
color of the light is very pleasing to the eye and gives a better rendition of 
colors than that obtained with the alternating current arc. 


This model, CRM, has been constructed especially for use with the 
Mazda lamp, and the design is calculated to give the greatest possible 
efficiency. The lamp housing and the dark chamber have been brought 
together to allow the lamp to be placed as close to the object as possible. 
No condensers are used in illuminating the opaque object, but the spe- 
cially corrected glass reflector placed back of the lamp directs the light upon 
the object in parallel rays. 

By means of special methods of ventilation the temperature of the 
outfit is kept sufficiently low, so that there is positively no danger of scorch- 
ing the specimen; neither does the apparatus become uncomfortably hot 
for operating. 

The instrument is constructed of heavy sheet metal by means of 
special forming tools, so that it has a pleasing appearance and the proper 
rigidity, at the same time being sufficiently light to make it readily port- 
able from place to place. It is finished throughout in black enamel with 
a dull lustre, which is both serviceable and appropriate in such an appar- 
atus. 

The area of the opaque object that can be projected is ordinarily 6 x 6 
inches, but by removing a plate from the bottom of the dark chamber 
the size can be increased to 7 x 7 inches. Much larger objects can be 
placed in position and shifted about so as to project any portion desired. 
The specimen is held in position against the bottom of the dark chamber 
by the object-holder, which is actuated by a spring-arm. To facilitate the 
rapid handling of small pictures, such as postcards, we supply two adjust- 
able carriers. 

The change from the projection of opaque objects to lantern slides, 
or vice versa, is made instantly by pushing in or pulling out a sliding 
rod located on the front of the dark chamber. This rod operates a shield 
in the dark chamber, which cuts off the light from the projection lens 
for opaque objects, or from the lens for lantern slide projection, and also 


29 














CRM 18—With changing device in position for opaque projection. 


brings the rear condenser, used for lantern slide projection, close to the 
lamp so that maximum efficiency of illumination for slides is secured. 
No movement of the lamp or lamp reflector is necessary in making the 
change, and there is consequently no jarring of the delicate lamp filaments 
during the operation. 


The projecting lenses are the Balo series, especially corrected for flat- 
ness of field and critical definition. The one for projecting the image 
of the opaque object is mounted on top of the dark chamber, together 
with a first-surface mirror which directs the light toward the screen and 
causes the picture to appear in correct position from left to right. The 
lens is 4 inches in diameter, of 15 or 18 inches focus, the selection 
depending on the projection distance and the size of the picture desired 
(see table, page 8). 

A lens is supplied for lantern slide projection, which is of the proper 
focal length to give approximately the same size picture as that obtained 


30 











with the projection lens for opaque objects. In order that the apparatus 
can be used conveniently for lantern slide projection at long distances, 
such as 50 feet, we have arranged for a supplementary lens to be used 
in conjunction with the regular lens, thus giving the effect of a long focus 
lens, without the disadvantage of a long supporting extension. (See price 
list). 

The mirror is fixed above the lens in an adjustable mount, which 
permits the images from both opaque object and lantern slide to be brought 
into coincidence on the screen. 

On account of the unavoidable loss of light in any projection of opaque 
objects, it is not possible to secure the same brilliancy as when using slides. 
Consequently, we would advise projecting a picture not larger than 10 feet 
square, if the distance will permit of such an arrangement. 

Particular attention should be given to the selection of a screen. A 
good quality, white, opaque screen, at least, should be used, and an alu- 
minum-coated screen is preferable. The latter, however, should not be 
used unless the audience can be placed within a total angle of about 60° 
from the center of the screen. 


Specifications 


Base—Consists of heavy sheet metal supports, front and rear, 10% in. 
wide, and carrying dark chamber at height of 514 in.; extreme length, 
231% in.; each foot is provided with screw hole for fastening Balopticon 
to table, if desired. 

Lamp House and Dark Chamber—One continuous with the other; meas- 
ure 91% in. wide by 15 in. long; lamp house is 17 in. high; dark chamber 
12% in.; light-tight and freely ventilated, constructed of double sheet 
metal walls, with an air space one inch in thickness between the two walls; 
roof of lamp house is fitted with our special patented ventilator; dark 
chamber provided with large, light-tight door on side convenient handle 
on outside of dark chamber at upper front controls shield by which 
light is cut off from opaque object lens or lantern slide lens, as desired 

Iluminant—1,000-watt, concentrated filament, gas-filled, Mazda stereop- 
ticon lamp, of special design; provided with ground and polished glass 
reflector, 8 in. in diameter, corrected to throw a parallel beam of light 
upon the specimen. 

Condensing System—Our regular double system, consisting of two plano- 
convex lenses, 41% in. in diameter, one mounted at the front of the dark 
chamber, the other on a sliding frame in dark chamber, for lantern 
slide projection only. 

Object Holder—-Square plate of sheet metal; held against opening in 
bottom of dark chamber by arm actuated by two strong springs; accom- 
modate objects of varying thickness and automatically brings them 
into proper plane for projection; opening in bottom of dark chamber 
permits area, 6 in. square, to be projected. (7 in. square by removing 
plate on bottom of dark chamber.) 

Slide Carrier—One double carrier, No. 4480, with elevating device. 


Post Card Carrier—Two adjustable carriers with wooden backs and 
frame, which fit object holder. 


ol 











Projection Lenses—Two of our new series of lenses, especially corrected 
to give a brilliant, flat field with the Mazda lamp; provided with rack 
and pinion adjustment; of such relative foci as to project images of 
approximately equal size from opaque objects and lantern slides; 
lens for opaque objects fitted with first-surface mirror to direct light 
to screen and cause picture to appear in proper position from left 
to right. 


Dimensions—Length, rear of lamp house to front of Jens for lantern slide 
projection, 27 in.; height to top of mirror, 33 in. 














Code Word | Cat. No. Specifications Price 











Decit CRM 15 | Combined Balopticon for projection of opaque ob- 
jects and lantern slides, with 4-in. diam., 15-in. 
focus lens for opaque objects and 15%-in. diam., 
8-in. focus lens for lantern slides ; 1000-watt Maz- 








da stereopticon. lamp:.;...«. .:.-.).5 0 eee $200.00 
Decov CRM 18 | Same as above, but with 18-in. focus lens for opaque 

objects and 154-in. diam., 10-in. focus lens for 

lantern. slides. 4.05.2. hija. seeds. oe Se 200.00 
Dedas 4379 Extra Post Card Holder °7....%.2... 42 1.75 





Long Distance Lantern Slide Projection 


In order to make it possible to use this apparatus for long distance 
lantern slide projection, we have developed a supplementary lens to be 
used in conjunction with the regular 15¢-in. diameter, 10-in. focus lens 
supplied on the CRM-18 outfit. This supplementary lens is furnished in 
a mounting, which fits between the extension adapter and the projection 
lens, giving the effect of a long focus lens without the long extension adapters 
which these would require. This combination of lenses makes it possible 
to use the apparatus up to a distance of 50 feet for lantern slide projection, 
producing a picture approximately 10 feet wide. 




















Code Word|Cat. No Specifications Price 
Dedet 4404 Supplementary Lens in mounting for use with 
15-in. diameter, 10-in. focus lens................. $11.50 





If the apparatus is to be used to a considerable extent, we suggest that 
a 2is-in. diameter, 10-in. focus projection lens be substituted for the 
regular 15¢-in. diameter lens, which would mean an appreciable increase 
in illumination. The extra charge for this lens would be $7.50, and a 
larger supplementary lens would be required. 











Code Word/Cat. No. Specifications Price 
Dediv 4406 Supplementary Lens in mounting for use with 
27.-in. diameter, 10-in. focus lens. ....4....,. 52.06 $14.50 





32 





BAUSCH & LOMB OPTICAL COMPANY 











Combined Balopticon for Projection 
at Long Distances 





CRM 25 


This new model is offered in order to meet the demand of those who 
must of necessity use an instrument at a greater projection distance than is 
practical with the CRM-18, and to those who desire to project a somewhat 
larger object than is possible with any other model herein listed. Although 
the regular projection area is 7 in. x 7 in., by removing a plate from the 
bottom of the dark chamber, it is possible to project areas up to 7 in. wide 
by 9 in. long. For those wishing to project only 6 in. x 6 in. areas, we can 
supply a special plate on order, to be attached to the bottom of the dark 
chamber. 

For these large areas, it is quite essential to use specially corrected and 
long focus lenses,—not only from the standpoint of image quality but 
because of the advantageous working distance from the screen. Conse- 
quently this equipment is offered only with the 25 in. focus, 4 in. diameter 
focus lens for opaque objects, and a 12 in. focus, 235 in. diameter lens for 


lantern slides. | 

This equipment will particularly appeal to Architectural and Mechanical 
Engineering Departments, Schools of Journalism and Advertising and others 
where blueprints, layouts, and large areas of varied description must be 
projected. 


33 

















When determining the size of the screen and the projection distance, 
one must take into consideration the longest side of the object, and reference 
should therefore be made to the following table, where the height of the 
picture is specified rather than the width as is usually customary with the 
shorter focus lenses. The table shows the height of the picture of the screen. 


























tee, Distance from lantern to screen 
Opening 20 ft. 25 ft. 30 ft. 35 ft. 40 ft. 45 ft. 
6” x 6” 44 5% 6% 8 9 10 
TS Te 54 614 734 94 10% 
apse Wl 6% 84 10% 











The general design and specifications of this model are the same as for 
the CRM models described on the preceding pages, except that the dark 
chamber is two inches longer and the reversing mirror is mounted in a 
prism shaped box back of the projection lens. 











Code Word Cat. No. Specifications Price 
Decuw CRM 25 | Combined Balopticon, with 5-in. diam., 25-in. 
focus lens for opaque objects and 2;3;-in. diam., 

12-in. focus lens for lantern slides ............ 290.00 








Other Equipment 


In addition to the outfits listed in the foregoing pages, our complete 
projection line includes the Model D Balopticon with optical bed, a high 
type of lantern slide instrument which is also admirable for work in physics 
laboratories and the like; the Convertible Balopticon, providing in its 
complete form for practically all types of optical projection; the Large 
Opaque Balopticon with double illuminant, for projecting objects up to 
12 inches square; and complete apparatus for microscopical projection, for 
drawing from microscopical objects, for work with polarized light, with the 
spectrum and with complementary colors. 

If interested in any of the above apparatus, write for a copy of our 
complete projection catalog, in which it is presented in full. 


34 








BAUSCH & LOMB OPTICAL COMPANY 








Balopticon Accessories 





Balo Projection Lenses 


This series of projection lenses has 
been designed to meet the requirements 
for lenses to project opaque objects as 
well as lantern slides. They are cor- 
rected for chromatic and spherical aber- 
ration and give critical definition to the 
extreme edges of the field. 


The lenses .of 158 and 2546 inches 
diameter are intended aecatalbedk: for 
lantern slide projection. The former, 
made in focal lengths up to 10 inches, 

: should be used only on outfits equipped 
with the arc lamp, while the latter should be used with the Mazda lamp 
and acetylene burner. The larger diameter lenses are especially con- 
structed for the projection of opaque objects. 


These lenses, very accurately mounted in heavy brass tubes with rack 
and pinion focusing adjustment, are finished in black and white engraving. 














Code Word Cat. No. | Diameter in Inches | Focus in Inches Price 
Dejey 4006 154 6 $ 15.00 
Dejiz 4008 15% 8 15.00 
Dejob 4010 1% 10 15.00 
Dejuc 4020 25 10 23.00 
Dekay 4022 Qa 12 23.00 
Dekez 4025 25 15 23.00 
Dekib 4028 255, 18 23.00 
Dekoc 4045 4 15 82.50 
Dekud 4048 4 18 82.50 
Delaz 4055 5 25 140.00 





Condensing Lenses 


Because of the quality of glass used and the superior workmanship our 
condensing lenses are considered standard. They are carefully annealed and 
finished. Although our patent, ventilated mount (see page 7) minimizes 
the danger of breakage, yet with all possible care condensers are still liable 
to break and it is well to have an extra set at hand. 

















Code Word | Cat. No. Specifications Price 
Deleb 5095 Plano-Convex lens, 4-in. diam.; rear lens of the 
Model CL system, unmounted................. $ 1.40 
Delic 5093 Plano-Convex lens 4-in. diam.; rear lens of the 
CRMFunmounted 20 ae cee ae cee 1.50 
Delod 5096 Plano-Convex lens, 4;-in. diam;. front lens of the 
Models B, BB, BC and C systems. Be sure to state 
focus of projection lens when ordering.......... 1.50 
Deluf 5102 Plano-Convex lens, 4;-in. diam.; rear lens of 
Home system, unmounted... 2.4.5. 44. a oo 1.50 
Demab 5104 Plano-Convex lens, 4;-in. diam.; front lens of 
Home and CRM systems. Be sure to state focus 
of projection lens when ordering............... 1.50 
Demec 5106 Plano-Convex lens, 4;-in. diam.; rear lens of 
Models B, BB, BC and C systems, unmounted .. 1.50 


30 











BAUSCH & LOMB OPTICAL COMPANY 














Illuminants 
Hand-feed Arc Lamp 


This lamp is carefully constructed, with 
screws and gears cut so as to prevent bind- 
ing even after being thoroughly heated. 
The carbons can be fed independently or 
simultaneously. A wide range of adjust- 
ment is provided for by accurate centering 
screws, and all adjusting and feeding screws 
are carefully insulated. 

Either direct or alternating current can 
be used, although the former is desirable as 
_.it gives greater illumination, is quieter in 

operation and more easily and accurately 
controlled. 


A rheostat must always be used with this lamp to regulate the 
current. 




















Code Word | Cat. No. Specifications Price 
Denuh 4464 Hand-feed Arc Lamp, with centering support; for 
use in small lamp houses, Model C type......... {$21.50 
Depad 4464L Same as above, but with long feeding and adjusting 
rods for use in large size lamp house............ .00 


Gas-filled Mazda Lamps 





No. 4466—400-Watt Gas-Filled Mazda Lamp. 


The new gas-filled Mazda lamps with concentrated filament, which have 
been especially developed for projection purposes, furnish an automatic, 
steady-burning and very efficient and economical light source for the simpler 
types of Balopticons. The efficiency varies from 0.8 watt per candle power 
in the lower wattages to 0.55 watt per candle power in the higher wattages. 
They are rated by the manufacturer to have a life of approximately 100 hours 
and we stand ready to replace any that may prove defective or burn for an 
unduly short period. If the Mazda burned only one-half its rated life, the 
cost of operating this type, including renewals, would be much less than the 


36 











BAUSCH & LOMB OPTICAL COMPANY 

















No. 4500 No. 4477 


cost of an arc lamp giving equal illumination, when the saving in current 
and carbon consumption is considered. In addition, the Mazda is entirely 
automatic, noiseless and steady in operation and its efficiency per number 
of amperes used is higher than that of the A. C. arc. These lamps are not 
recommended for microscopical projection as they are not sufficiently con- 
centrated or homogeneous. 





No 4476—1000-Watt Gas-Filled Mazda Lamp 


The 400-watt and 1000-watt lamps are intended for use on regular circuits 
of 110-volts or 220-volts when used with resistance; the 30-volt, 14-ampere 
lamp can be used on individual lighting plants or on the regular circuit, 
when used in series with a transformer or rheostat, while the 6-volt lamp 
is intended for use with a storage battery. 


37 





BAUSCH & LOMB OPTICAL COMPANY 























Code Word | Cat. No. ! Specifications Price 
Depig 4466 400-watt Mazda Lamp with gas-filled globe, re- 

flector on support, 15 ft. of extension cable, con- 

necting plug and switch. ......;2. 2440s eee $18.50 
Depoh 4479 400-watt Mazda Lamp, bulb only............ net 3.65 
Depuj 4476 1000-watt Mazda Lamp, with gas-filled globe on 

support with glass reflector, 4 feet of extension 

cord and pass-through awitéh .. sc. # eee 27.75 
Deraj 4478 1000-watt Mazda Lamp with gas-filled globe, clear; 

bulb: only.058 >... oe fe oe net (Py b) 
Dereg 4500 6-volt Mazda Lamp for use with storage battery, 


with silvered globe, supplementary condenser in 
mounting, 6 feet of connecting cord with switch and 











lugs for connecting storage battery............. 13.50 
Derth 4504 6-volt, 24-watt Mazda lamp, silvered; bulb only net 1.25 
Deroj 4477 30- volt, 14-ampere Mazda Lamp, with gas-filled | — 

globe on support with glass reflector, 4 feet of ex- 

tension cord and pass-through switch... :. ¢2aenee 22.50 
Deruk 4492 30-volt, 14-ampere lamp; bulb only........... net 5.50 
Deseh 4536 600-watt, 110-volt tubular-shaped Mazda _ lamp; 

bulb only hig whe cata segs es net 5.50 








NOTE—On account of its size the 1000-watt lamp can only be used in the large, light 


tight model lamp houses. 
All illuminants listed above are fitted with sliding base suitable for use on such 
Balopticons as Model C or CL. 


Acetylene Lamp 


Acetylene is a convenient illuminant, as it 
is easily obtained or prepared and is portable. 
The illumination is sufficient for work at com- 
paratively short distances. Our lamp has a 
powerful double jet, mounted in front of our 

_ patent, optical mirror of silvered glass, which 
concentrates and steadies the light, nearly 
doubling the illumination. For the best result 
obtainable with this lamp a 10-inch focus pro- 

: -jection lens, of 23-inch diameter, giving an 

image 6 feet are at a distance of 20 feet, shenld be used. This burner 
consumes 2 cubic feet of gas per hour. 











Code Word | Cat. No. Specifications Price 


Desij 4467 Acetylene Lamp with reflector and 6 feet of rubber 
tubing (designed particularly foruse on Model C) | $13.00 














38 





BAUSCH & LOMB OPTICAL COMPANY 














Rheostats for Arc Lamps 


With every arc lamp there must be used 
a rheostat, selected according to the voltage 
available and the number of amperes re- 
quired. ) 

We construct our rheostats to meet the 

No. 4452—414-Ampere Rheostat strictest requirements of fire boards and 
underwriters and they have been approved 
by the National Board of Fire Underwriters’ Laboratory of Chicago. The 
wire in the resistance coils has practically no temperature coefficient and 
will not deteriorate with frequent heating and cooling. The cases are of 
perforated metal thus providing for the freest possible air circulation among 
the coils. There are no exposed contact points, and every means of insuring 
safety has been taken advantage of. 

The coils in rheostats of 15 amperes capacity and over are wound on 
asbestos board strips to prevent sagging or possible contact between coils. 
The coils in the 4144-ampere rheostats are carried on porcelain spools. 

The 414-ampere rheostats can be used satisfactorily with the electric 
wiring usually found in private houses, connecting with the ordinary lamp 
socket. Those of higher capacity generally require special wiring. 





When ordering be sure to specify voltage. 





No. 4450—15-Ampere Rheostat No. 4456—15 to 35-Ampere 
Rheostat 


39 








BAUSCH & LOMB OPTICAL COMPANY 





























Code Word | Cat. No. Specifications Price 
Desok 4450 Fixed Form, 15 amperes, 110 volts............ $10.25 
Desul 4451 ss 15 -amperes, 220.-volts.. co) eae 27.00 
Detol 4452 ‘ 414 amperes, 110 volts, with cord, 

plug and pass through switch .......)./) 0. ase 8.75 
Detum 4453 Fixed Form, 4/4 amperes, 220 volts with cord, plug 

and pass through switch...5, 5. 0 0. 12.50 
Devaj 4458 Adjustable Form, 5-10 and 15 amperes, 110 volts. 18.00 
Devek 4454 ts 15 to 25 amperes, 110 volts. 27.00 
Devil 4455 3 a 15 to 25 amperes, 220 volts. 37.50 
Devom 4456 ie 15 to 35 amperes, 110 volts. 50.00 
Devun 4460 . Ly 15 to 35 amperes, 220 volts. 62.50 











Transformers and Resistances for Mazda Lamps 


Any Mazda lamp, used on an electrical circuit whose voltage materially 
exceeds that for which the lamp is rated, must be provided with a suitable 
transformer or resistance to be connected with the lamp in order to reduce 
the voltage to that for which the lamp is rated. 

It has not been found practical to make these concentrated high power 
lamps for 220 volts or higher; hence, where high voltage prevails, the 110- 
volt lamps, as well as the 6 and 30-volt ones, must be used with a resistance. 

For the low voltage lamps, particularly those drawing rather high am- 
perage, a transformer should be used wherever alternating current is avail- 
able, as with this device the rate of current consumption on the main line 
is reduced to the point where all of the low volt lamps listed, with the ex- 
ception of the 30-volt, 30-ampere lamp, may be connected with the regular 
lighting socket. When operating on direct current a resistance must be used 
and an outlet, with an ampere capacity equivalent to that for which the 
lamp is rated, provided. 





























Code Word | Cat. No. Specifications Price 
Dewak 4431 Transformer for 6-volt, 4-ampere lamp; 110 volts, 
60 cycles, alternating current. .....:)..) 222.98 $ 7.50 
Dewel 4433 Transformer for 6-volt, 4-ampere lamp; 220 volts, 
60 cycles, alternating current.................. 11.25 
Dewim 4434 Resistance for 6-volt, 4-ampere lamp; 110 volts, 
direct current...) io... See ee 8.75 
Dewon 4436 Resistance for 6-volt, 4-ampere lamp; 220 volts, 
direct current. , 2... ..).s¢5n 500. 12.50 
Dewup 4497 Transformer for 6-volt, 18-ampere lamp; 110 volts, 
60 cycles, alternating current.................. 10.00 
Dexal 4438 Resistance for 6-volt, 18-ampere lamp; 110 volts, 
direct current: . 2.05.4 .04 ) Gr 18.00 
Dexem 4496 220-volt Resistance for 400-watt lamp.. ....... 9.50 
Dexin 4498 220-volt Resistance for 1000-watt lamp.......... 14.00 
Dexop 4499 30-volt, 14-ampere Transformer, for use on 110- 
volt, alternating current, with 15 feet of extension 
cord, switch and plug on primary cord from lamp 
on secondary sidé@..5. 20... 23 ec. . ee er 17.50 
Dexur 4469 Rheostat for use on 110-volt, direct current with 
30-volt, 14-ampere lamp with 2 feet of connecting 
cord attached to terminals. .......,) ssi. eee 22.00. 





40 





BAUSCH & LOMB OPTICAL COMPANY 








































































































Cable 
“Code Word | Cat. No. Specifications Price 
Cable 
Deyam 5179 Rubber Covered Twin Cable, No. 12 copper wire, 
HOVE o amperes pers (OOL mae Lee eee cre. one $ .20 
Deyen 5180 Rubber Covered Twin Cable, No. 10 copper wire, 
fori ZO. AMperes, Per 100t. wc oe ee es oS 725 
Deyitp 5184 No. 14 Rubber Covered Portable Lamp Cord, per 
LOOUET nels EE ENA NAT Ee ce hee a 12 
Deyor 5185 No. 16 Rubber Covered Portable Lamp Cord, per 
LOOT Meira ce ae eg ne FONE Bal ie .08 
Carbons 
Code Word | Cat. No. Specifications Price 
Carbons 
Deyus 4470 Cored Carbons, ;% in. diameter, 6 inches long, per 
LED Serre a Pe eRe, Moen See ee revue ene, $ .40 
Dezan 4471 Cored Carbons, 7% in. diameter, 6 inches long, per 
GTA spam ares e ent Nees pete) Mie Ney te cv aie 38 
Dezep 4472 Cored Carbons, 3; in. diameter, 6 inches long, per 
LCL ee ee St cE Maes ene & Dae HE ican cn, .40 
Dezir 4473 Cored Carbons, 14 in. diameter, 6 inches long, per 
A Ok ee ae Bet a Or EME ie Aa MO Ln Ra CEP ae nak oe Waco .38 
Dezos | 4437 Solid Carbons, 4mm diameter, 6 inches long, each 04 
Dezut | 4482 Solid Carbons, 5mm diameter, 6 inches long, each .04 
Acetylene Tank 
Code Word | Cat. No. Specifications Price 
Dhabn 4483 Acetylene Tank, 10 cubic feet capacity.......... $13.00 


Acetylene Generator 


This is a very compact generator, with a capacity of one pound of 
carbide. It is fitted with a needle valve, etc., for control of the gas flow. 
































Code Word Cat. No. Specifications Price 
Dhacp 4587 Acetylene Generator as described; dimensions, 
approxamately® (x91 Ins. ee eee $14.00 





4] 














BAUSCH & LOMB OPTICAL COMPANY 














Slide Carriers 


A satisfactory slide carrier, both con- 
venient and durable, is essential to a high 
grade projection apparatus. We supply 
several which have given such satisfac- 
tion. Particular attention is called to 
No. 4449, our new rapid-changing 

Rapid-Changing Slide slide carrier, which is a double carrier 

Carrier, No. 4449. . ; 

operated entirely from one side. As a 

new slide is fed forward, the preceding slide is automatically returned, and a 

metal shield, which travels with the slide, obliterates all movement of the 

slide on the screen, so noticeable in ordinary double carriers and other types 

of slide changers. This approximates a dissolving effect, thereby relieving 
all eyestrain. 3 

Two carriers, Nos. 4430 and 4432, = 
are neatly finished wooden frames, pro- fe 
vided with an automatic elevating de- 
vice. This consists of loosely fitted metal 
pins beneath the center of the slides, 
which engage with an inclined plane at 
the end of the sliding movement, raising the slide so that it may be easily 
lifted out by its margin. No. 4430 is regularly supplied with our lantern 
slide equipments. 

We also make a convenient post card carrier for our apparatus project- 
ing opaque objects. 








Slide Carrier, No. 4480. 























Code Word | Cat. No. Specifications Price 
Dhish 4430 Slide Carrier, for two 344 x 4-inch slides with auto- $2.00 
matic elevating device. 7s, .25. -. An. ee 
Dhit} 4432 Double Slide Carrier, for either 3144 x 344 or 34 x 25 
4-inch slides with automatic elevating device. ... 
Dhivk 4449 Rapid-Changing Slide Carrier................. 5.00 








Note—The semi-dissolving slide carrier, No. 4449, may be substituted on any equip- 
ment regularly supplied with No. 4430 for $3.00 additional. 


42z 





BAUSCH & LOMB OPTICAL COMPANY 











Balopticon Tables 





No. 4259 


To provide a suitable means of supporting the Balopticon we have 
developed a line of supporting tables, all of which are of a convenient height 
for operating the Balopticon and of a proper height for clearing the heads 
of the audience. 


No. 4259 stand, made of angle iron, is very rigid. 48 inches high. Wooden 
top 30 x 12 in. Very desirable for the smaller types of Balopticons. 


Stand No. 4257 is made of angle iron, strongly braced, and has a wooden 
top, the front of which may be raised or lowered. One of the unique features 
of this stand is that it may be folded up when not in use and stored in any 
small closet. It is of course folded when shipped. The front legs are 
fitted with casters, so that by lifting rear legs free of the floor it may be 
easily moved from place to place. Because of the method of bracing it is 
extremely rigid, and is recommended for such outfits as the CL and CRM. 


43 

















Folding Balopticon Table No. 4257 in Two Positions 








No. 4253 stand is made with a heavy cast iron base with supporting 
columns, and a cast iron frame-work upholding the wooden top, which is 
provided with elevating screws at the front. This table is particularly rec- 
ommended for such apparatus as the Convertible. 

















Specifications 








Code Word | Cat. No. 
Dhixm 4259 
Dhizp 4257 
Dhobs 4253 











Balopticon Table of metal, 48 in. high; top of wood, 
30 x 12 inchés . 00 ca dS ee 
Folding Balopticon Table, 47 in. high, with wood- 
en top 32 x 19-in. |. 8 ee 
Balopticon Table 44-in. high with strong casti on 
bare and frame, and heavy 40x 17-in. wooden top; 
space beneath for adding cabinet, if desired; 
provided with casters and leveling screws ...... 





44 


Price 





$15.00 
27.50 


2, 
CHEST RS 


OMe, 
BSD 
E 
c 5 
< 2D, 
, ay 








BAUSCH & LOMB OPTICAL COMPANY 


oF. 





Kons 
SOFT 


oO 


CHESTER 


“*, 





Balopticon Table, No. 4258, with No. 4456 Rheostat 
and Knife Switch as supplied with Convertible Balopticon 


45 





| BAUSCH & LOMB OPTICAL COMPANY 








Screens 


Ordinary sheeting, or common cloth, is too translucent to furnish a 
satisfactory screen for projection work. Our screens are all made of heavy 








cloth, specially prepared and as nearly opaque as possible. ‘They are 

mounted on spring rollers. 

Code Word | Cat. No. Specifications Price 
Dhoct 4420 Screen, Gfeetx 6feet,each................. net | $ 8.75 
Dhodv 4421 t CSRS ETE DS ETE: Ee net 12.00 
Dhofw 4422 . auger. Sera ak Cees wert net 15.00 
Dhohy 4423 : Qe Oe Oe puke alee ce toe en net 24.00 
Dhojz 4425 y 10S RIDES Se ee aie eee net | 28.50 
Dhokb 4426 ¥ 120" x12 Rs te... ae ae net 55.00 











Larger sizes will be quoted upon request. 


Aluminum Screens 


These screens are made of heavy material with a metallic surface. They 
give a much more brilliant image than the ordinary screen and are recom- 
mended in all cases, but especially will their superiority be noted in project- 
ing opaque objects, microscopic specimens and in all work requiring brilliant 
illumination. Owing to their narrower field, however, due to the high re- 
flecting surface, they should be used only when the audience can be seated 
within an included angle of 60 degrees from the center of the screen. 











CodeW ord 
































Cat. No. | Size Price ||CodeWord) Cat. No. Size Price 
Dhold 4420A 6x6ft.| $11.50 | Dhopg 4423A 9x 9ft $30.00 
Dhomd 4421A | 7x7 ft. 15.50 Dhorh 4425A | 10x10ft 35.00 
Dhonj 4422A = 8 x 8 ft. 20.00 Dhosj 4426A | 12x12ft. 65.00 


These screens are supplied for portable outfits. 


Sateen Screens 


Sateen is as nearly 


opaque and highly reflecting a material as can be obtained, which at the 
same time is suitable for packing in a case. These screens are provided with 
eyelets for stretching and have reinforced borders. 


Code Word 








Cat. No. Specifications Price 
Dhotk 4420S Screen, 6 .x 6 feetci:.:.:..... ao pee net | $ 7.00 
Dhovl 4421S £ 744 x 7146 feet:..4:4.... 50 ee net 10.00 
Dhowm 4423S oe 9° °x 9° ‘feet..cc..5 4.42 ee net 18.00 
Dhoxn 4426S if 12: x12. feet... ..4... 2.2; .. =. net 24.00 








46 





A, Model Balopticon 
Accessories, Balopticon 
Acetylene Generator 
Acetylene Lamp 
Acetylene Tank 
Aluminum Screens . 
Are Lamp, Hand Feed 
Balo Projection Lenses 
Balopticons 

Combined 

Combined Junior 

Double Dissolving 

Home . 

Model A 

Model B 

Model BB 

Model BC 

Model C 

Model CL 

Model CRM . 

Portable Model B 
B, Model Balopticon 
BB, Model, Dissolving Baloouicon 
BC, Model Balopticon . : 
Balopticon Accessories . 
Balopticon Tables 
C, Model Balopticon 
Cable 
Carbons . 
Carriers, Slide 
Carriers, Post Card 
CL, Model Balopticon . 
Combined Balopticon, CRM . 
Condensing Lenses . 
Construction, General . 
CRM Balopticon 
Dissolver, Iris 
Dissolving Rheostat 
Dissolving Switch 
Gas-filled Mazda Lamps 
Generator, Acetylene 
Hand-Feed Arc Lamp . 
Home Balopticon 
Iluminants 


Acetylene Lamp . . 
Are Lamp, Hand-Feed 











Mazda Lamps, Gas Filled 
Special for Model B . 

Iris Dissolver 

Lamps (see Tlaminants 


Lecturers’ Special Portable Outfit, 


Model B 
Lenses, Balo Projection 
Lenses, Condensing . 
Long Distance Lantern Slide 
Projection 
Magnification Tables 
Lantern Slide 
Opaque Objects 
Model A Balopticon 
Model B Balopticon 
Model BB Balopticon . 
Model BC Balopticon . 
Model C Balopticon 
Model CL Balopticon . 
Model CRM Balopticon 





Opaque Object Projection Tables 


Portable Outfit, Model B . 
Post Card Carriers . 
Projection Lenses, Balo 
Projection, Stereoscopic, with 
Model BB . 

Projection Tables ; 
Resistance for Mazda Lamps 
Rheostats 
Rheostat, Bicol’ 
Sateen Screen 
Screens 

Aluminum 

Sateen . 

White Opaque 
Slide Carriers 
Special Traveling Outfit 
Stereoscopic Projection with 

Model BB . 

Switch, Dissolving . 
Tables, Balopticon . 
Tables, Projection 
Termsii) 2 
Traveling Outfit, Model B 
White Opaque Screens . 


36-38 


22, 25 


7, 35 


Other Products 


We append a partial list of our other products of possible interest to 
the reader of this catalog. 


Centrifuges Ophthalmic Lenses 

Colorimeters Optical Glass 

Drawing Apparatus Optical Machinery 

Field Glasses Photographic Lenses and Shutters 
(Stereo-Prism Binoculars) Photomicrographic Apparatus 

Magnifiers Reading Glasses 

Micro Projectors Refractometers 

Microscopes and Accessories Searchlight Reflectors 

Microtomes Saccharimeters 

Ophthalmic Instruments Spectacle and Eyeglass Frames, 


Mountings and Cases 


We shall be glad to furnish literature or information on any of the same 
upon request. 


48 





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